The assessment of renal function in small animals is of interest both to veterinary practitioners and research organisations, especially those investigating the possible effects of drugs developed for humans or companion animals, which might be destructive for kidneys. For veterinarians, one primary concern is the early diagnosis of chronic kidney disease (CKD), defined as primary renal disease present for an extended period of time. Sam Williams and Ludovic Pelligand from Delta Dot studies this casus, presenting clinical trials data and the importance the earliest-possible identification.